My ex , his new girlfriend and our children?

i have 3 year old twins with my ex with haven't talked in 2 years , and he hasn't been a father to them he has a live in girlfriend of over 1 year who also has a 3 year old daughter from a previous relationship so while with her his family requested them to visit a few times, but now once again they have went a month without requesting to see them this happens all the time and i think its unhealthily.....Now i was not receiving my child support payments for 3 months because he claims to have lost his job....but when i called the Child Support unit in New york...they stated he took a leave of absence....But yesterday i received 2 support payments which they said came from unemployment that hes collecting....Im a but confused if hes collecting unemployment how would he be on a leave of absence??? What should i do about this situation he has been sending me back and fourth to court to have his payments reduced will that happen??